Me, I blame the end of the Cold War. With a common, looming enemy in competition, Americans had more stake in being cohesive. The 50’s through 80’s were the era of the Cold War liberal, the Peace Corps and Kennedy … but also the Cold War conservative, Nixon going to China. America had a stake in projecting an image that was tough, but compassionate and fair. Atrocities in Vietnam were a problem because the USSR could make political hay out of them in the rest of the world. Gaertner and Dovidio’s “common ingroup identity model” with its provisions about a common enemy perfectly captures the way that liberals and conservatives had to work together as Americans in the Cold War.

The current enemy in the War on Terror is an ideology. But not everyone sees it this way; the default response is to think the war is against all of Islam, or other conflated categories like Arabs (would be nice to have data on this, but it’s fairly evident from the Ground Zero mosque incident). If you see being Muslim as the problem, it’s a fairly unchangeable status as opposed to an ideology. So you worry less about how the country looks to undecided people, even in the face of counterproductive policies that work to create more extremism. Looking tough takes precedence over looking fair or kind.

If I’m right on this, then a shift in the terms of foreign policy has had profound repercussions for domestic policy. Or, we could just blame the Internet instead. That’s always fun to do …